maria-developers team mailing list archive

[Sergei Golubchik <serg@xxxxxxxxxxx>]

Hi, Holyfoot!

On Oct 06, holyfoot@xxxxxxxxxxxx wrote:
> revision-id: c934b5e661b19b7934d1a9af40afc70b727c2273 (mariadb-10.1.7-64-gc934b5e)
> parent(s): 90f2c822469a4f88f882ba8974e790f0fb0b2702
> committer: Alexey Botchkov
> timestamp: 2015-10-06 14:02:29 +0500
> message:
> 
> MDEV-8842 add group support to pam_user_map module.
> Added to the pam_user_map module.

Right, thanks.
A couple of comments, see below.

> diff --git a/plugin/auth_pam/mapper/pam_user_map.c b/plugin/auth_pam/mapper/pam_user_map.c
> index e73ab6d..0787b1c 100644
> --- a/plugin/auth_pam/mapper/pam_user_map.c
> +++ b/plugin/auth_pam/mapper/pam_user_map.c
...
> +  /*
> +    So below we get the buffer of the NGROUPS_MAX size
> +    which can take 256K on some systems.
> +    It supposed to be working differently - we'd get
> +    the 'ng' from the getgrouplist() and alloc the respective
> +    size, but the problem is a bug in getgrouplist().
> +    The glibc 2.3.2 implementation of this function  is  broken:
> +    it overwrites memory when the actual number of groups is larger
> +    than *ngroups.
> +  */

Forget 2.3.2, use it as it was supposed to be used.
Our oldest builder uses glibc-2.5

> +  (void) getgrouplist(user, user_group_id, groups, &ng);
> +  for (i= 0; i < ng; i++)
> +  {
> +    struct group *g;
> +    if ((g= getgrgid(groups[i])) == NULL)
> +      return 0;
> +    if (g->gr_gid == group_id)
> +      return 1;

Eh? Why don't you compare group_id with groups[i] directly ?

Regards,
Sergei